The Measurement of Information
The maximum uncertainty: A situation which represents the maximum uncertainty is when a question can be equally answered ’Yes’ or ’No’.
The unit of information ’bit’: In information theory, an answer ’Yes’ or ’No’ to a question, (e.g., is the new born baby a boy ?) is precisely defined as one ’bit’ of information which is derived from the digits of ’1’ and ’0’.
The measurement: With two questions, one out of four possibilities may be decided; with three questions one out of eight, and so on. So the base 2 logarithm of the possible number of answer can be used as a measure of information, i.e.,
Information (bits) I = Log 2 n (n: the numbers of alternatives)